Right to be heard secures oral and written submissions; absent appellants face ex parte disposal but may seek restoration. The rule entitles appellants to be heard, permits the Board to be heard with an appellant reply, allows supplementation of written submissions by time bound oral arguments, authorises temporary substitution of Members to hear the Board, permits ex parte disposal if the appellant does not appear, and requires setting aside and restoring an appeal if sufficient cause for non appearance is later shown.